反应详情

To a solution of compound 51 (1.0 g, 2.5 mmol) in dry dichloromethane (10 mL) at −20° C. was added iso-butylchloroformate (450 mg, 3.3 mmol). After 20 min at −20° C. diethylamine (4 mL) was added and the reaction was allowed to warm to room temperature. After 1.5 hrs the solvent was evaporated and the reaction mixture was partitioned between ethyl acetate and water. The ethyl acetate was washed with water and brine and dried over MgSO4 and removed by evaporation. The crude product was purified by silica gel chromatography (0-60% ethyl acetate in heptanes) to give the product (compound 52) as white needles (800 mg, 73%).

1. customAfter 1.5 hrs the solvent was evaporated
2. customthe reaction mixture was partitioned between ethyl acetate and water
3. washThe ethyl acetate was washed with water and brine
4. dry with materialdried over MgSO4
5. customremoved by evaporation
6. customThe crude product was purified by silica gel chromatography (0-60% ethyl acetate in heptanes)